I bought 20 broken glass solar panels to repair and use on our off grid homestead. I am sharing my experience with broken solar panels.
Normally when you buy freshly broken solar panels they should produce about 80 - 95% of their rated capacity. But the longer they sit outside, the lower this number will be.
The solar cells are protected from the elements by the glass on top. When this glass gets broken the cells underneath start to degrade from the water which reaches then. With time corrosion sets in and can destroy your solar panel.
I bought these from a large solar panel company trusting that their listing was true and honest. But it was not. The panels I received were poorly packaged and damaged worse in shipping. The panels were burnt through in places from something other than being broken. And these panels had been sitting around outside for years after they were broken which degraded them badly.
You can see the rust under the glass from long term corrosion.
I have two broken solar panels in comparison of my own which are still working well after years of service. My large panel got broken about 4 years ago by a flying stone. I never repaired it and it is still working today.
I have a folding solar panel which got broken by a stone when it was in use on an RV and it still works well.
If you buy broken solar panels be sure to communicate well with the seller and make sure they are honest. Get more photos if possible.
When you received your broken solar panels protect them from the elements right away. The longer they sit out, the worse they can get. Use solar panel repair epoxy which you can buy online.